To provide a locking device lockable regardless of the size of a clearance between closing members, small and easily after-fitted, locking only when an opening is properly closed, and arrangeable in a position separated from a main lock.
A sash door 3 capable of closing the opening of a door is installed on the outdoor side, and a sash door 2 (an indoor side sash door) is installed on the indoor side. The sash door 2 is provided with a lock mechanism 9 capable of retracting back and forth relative to the sash door 3, and the sash door 3 is provided with a regulating plate 6 capable of abutting on the lock mechanism 9. When the sash door 3 and sash door 2 are in the closed state, the lock mechanism 9 is allowed to abut on the regulating plate 6 to lock the sash door 3. The sash door 2 is provided with an error detecting plate 27 for detecting the mutual opened/closed state of the sash door 2 and sash door 3, a lock detecting plate 29 abutting on the regulating plate 6 to detect the normal locked state of the lock mechanism 9 and regulating plate 6, and a locking plate 28 abutting to regulate the opening of the sash door 3 when the regulating plate 6 is inputted in the opening direction.
SAITO MASAAKI
NAGANO SHIGERU
YAMAGUCHI MORIO
Nishimura Kimiyoshi